Rattling from Door Panel Near Side Mirrors

Hello, I have vibrations coming from my door panels, which seem very loose. Can I fix or reinforce them? I have a 2021 outback with 38k miles on it.

I told the dealership a long time ago they were rattling and they told me there was nothing that could be done. I'm attempting to replace the base model OEM speakers in the next couple weeks but wanted to see if there was something I can look for/replace to help with the vibration and overall looseness